Perjeta Approved for Neoadjuvant Treatment of Early Stage HER2-Positive Breast Cancer The U.S. Food and Drug Administration (FDA) has granted accelerated approval to Perjeta® (pertuzumab) for the neoadjuvant treatment of early stage breast cancer before surgery. This is the first drug approved for the neoadjuvant treatment of breast cancer.

Breast cancer is the second leading cause of cancer-related death among women. This year an estimated 226,870 women will be diagnosed with breast cancer, and 39,510 will die from the disease. Approximately 20-25 percent of breast cancers overexpress (make too much of) the human epidermal growth factor receptor 2 (HER2), which is part of a biological pathway involved in growth and spread of cancer cells.

Perjeta is given intravenously and targets the HER2 protein. It was approved in 2012 for the treatment of patients with advanced or late-stage (metastatic) HER2-positive breast cancer. Its new use is intended for patients with HER2-positive, locally advanced, inflammatory or early stage breast cancer (tumor greater than 2 cm in diameter or with positive lymph nodes) who are at high risk of having their cancer return or spread (metastasize) or of dying from the disease. It is to be used in combination with Herceptin® (trastuzumab) and other chemotherapy prior to surgery and, depending upon the treatment regimen used, may be followed by chemotherapy after surgery. Following surgery, patients should continue to receive Herceptin to complete one year of treatment.

The approval was based on data from a study that included 417 patients who were randomly assigned to receive one of four neoadjuvant treatment regimens: Hercpetin plus docetaxel; Perjeta plus Herceptin and docetaxel; Perjeta plus Herceptin; or Perjeta plus docetaxel. About 39 percent of patients who received Perjeta plus Herceptin and docetaxel achieved pathologic complete response (pCR) compared with about 21 percent who received Herceptin plus docetaxel. It is unknown, at this time, if the improvement in pathologic complete response will lead to fewer recurrences or an improvement in survival.

The most common side effects reported in participants receiving Perjeta plus Herceptin and docetaxel were hair loss, diarrhea, nausea and a decrease in infection-fighting white blood cells. Other significant side effects included decreased cardiac function, infusion-related reactions, hypersensitivity reactions and anaphylaxis.

The FDA reviewed Perjeta’s use for neoadjuvant treatment under the agency’s priority review program, which provides for an expedited review of drugs that may offer major advances in treatment.

A confirmatory trial is being conducted in patients with HER2-positive breast cancer who had prior breast cancer surgery and are at high risk of having their cancer return. More than 4,800 participants are enrolled in this trial, which will provide further data on efficacy, safety and long-term outcomes. Results are expected in 2016.